• Title/Summary/Keyword: Dominant Species

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Weed Population Distribution and Change of Dominant Weed Species in Paddy Field of Southern Gyeonggi Region (경기 남부지역 논잡초 발생분포 및 군락변화)

  • Park, Jungsoo;Won, Taejin;Roh, Ahnsung;Jang, Jaeeun;Kim, Heedong
    • Weed & Turfgrass Science
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    • v.3 no.2
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    • pp.86-94
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    • 2014
  • Survey was carried out in paddy fields to investigate the dominance of weed species and weed occurrence on 200 fields of southern Gyeonggi region in Korea during the year 2013. We observed 3 species of grass, 5 species of sedge, and 11 species of broadleaf and other weeds. The most dominant weed species was Eleocharis kuroguwai, followed by Echinochloa crus-galli, Sagittaria trifolia, Monochoria vaginalis, Scirpus juncoides and Bidens tripartita. The dominance value of E. kuroguwai and B. tripartita decreased compared to the survey results performed in 2005 but that of M. vaginalis, S. juncoides, S. trifolia and E. crus-galli increased. Weed occurrence increased from 2.83 g in 2005 to 3.51 g in 2013 based on weed dry weight per $m^2$. Occurrence ratio of annual weeds to perennial weeds changed from 45.2% : 54.8% in 2005 to 45.8% : 54.2% in 2013. If we analyze dominance of weed species based on the rice transplanting timing, E. kuroguwai and E. crus-galli were the most dominant weed species at mid-May transplanting, and M. vaginalis and S. juncoides were the most dominant weed species at late- May transplanting, and M. vaginalis and E. kuroguwai were the most dominant weed species at early-June transplanting. Since paddy weeds resistant to sulfonylurea herbicides are expected to be continuously increased, the regular monitoring of their occurrence and efficient control methods should be considered in future.

Three Alternaria Species Pathogenic to Sunflower

  • Cho, Hye-Sun;Yu, Seung-Hun
    • The Plant Pathology Journal
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    • v.16 no.6
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    • pp.331-334
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    • 2000
  • Alternaria helianthi and two unreported species of Alternaria in Korea were isolated from lesions of Alternaria leaf spot disease of sunflower. The unrecorded species of Alternaria were identified as A. helianthinficients and A. protenta based on the morphological characteristics of conidiophores and conidia. A. helianthi was the dominant species, although all the three species were associated with the disease. A. helianthi, A. helianthinficiens and A. protenta produced similar symptoms on detached sunflower leaves. This is the first report of A. helianthinficiens and A. protenta pathogenic on sunflower in Korea.

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Distribution of Ichthyoplankton in the Adjacent Waters of Yousu (여수주변해역의 치자어 분포)

  • YOO Jae Myung;LEE Eun Kyung;KIM Sung
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.3
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    • pp.295-302
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    • 1999
  • To study the distribution of ichthyoplankton in the adjacent waters of Yousu, ichthyoplankton were sampled 4 times (September 1996, November 1996, February 1997 and May 1997). Four species of fish eggs and twenty-four species of fish larvae were identified. Among fish eggs, Engraulis japonicus eggs were the dominant species comprising $80.6\%$ of the total fish eggs collected, followed by Callionymidae spp. $1.6\%$, Konosirus punctatus and Maurolicus muelleri occupied below $1.0\%$ respectively, while $17.8\%$ were unidentified. Most larval fish species were found in September (17 species). In fish larvae, Callionymidae spp. was the dominant species occupying $25.7\%$ of total fish larvae collected and than followed by Gobiidae spp. $23.5\%$, Sillago japonica $17.2\%$ Engraulis japonicus $12.2\%$, Omobranchus elegans $9.9\%$ and the unidentified species were less than $2.0\%$. The larvae fish species collected in this study area were comprising the coastal sedentary species (Gobiidae, Callionymidae, Hexagrammos otakii and io on), and the warm water species (Auxis spp. and Coryphaena hipurus and Pomacentridae spp.) which were appearing by warm water current flowing near the costal area of Cheju Island.

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Relationship between Ectomycorrhizal Fruiting Bodies and Climatic and Environmental Factors in Naejangsan National Park

  • Jang, Seog-Ki;Kim, Sang-Wook
    • Mycobiology
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    • v.43 no.2
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    • pp.122-130
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    • 2015
  • We collected and identified 5,721 ectomycorrhizal fruiting bodies (EcM) from Naejangsan National Park from June 2004 to 2013, belonging to 1 phylum, 1 class, 6 orders, 19 families, 40 genera, and 196 species. Of these, 2,249 individuals were identified as 89 species belonging to 11 genera in 7 families in the Agaricales; 1,511 were identified as 43 species belonging to 2 genera in 1 family in the Russulales; 1,132 were identified as 50 species belonging to 21 genera in 6 families in the Boletales; 793 were identified as 8 species belonging to 3 genera in 2 families in the Cantharellales; 29 were identified as 3 species belonging to 2 genera in 2 families in the Thelephorales; and 7 were identified as 3 species belonging to 1 genus in 1 family in the Gomphales. Thus, most of the EcMs identified belonged to the following 3 orders: Agaricales, Russulales, and Boletales. Russulaceae were most common (43 species), followed by Boletaceae (39 species), and Amanitaceae (27 species); most individuals were Russulaceae (1,511), followed by Hydnagiaceae (1,071) and Boletaceae (804). The monthly distribution showed that the greatest number of individuals and species of EcM, including the dominant ones, occur around July~September at an elevation of 200~299 m, diminishing markedly above 600 m. The greatest number of individuals and species, including the dominant ones, were collected in the period with average temperatures $25.0{\sim}26.9^{\circ}C$, lows of $21.0{\sim}22.9^{\circ}C$, and highs of $30.0{\sim}31.9^{\circ}C$, relative humidity > 76%, and rainfall > 400 mm.

Seasonal Variation in Species Composition of Fish Collected by Trammel Net Around Dokdo, East Sea of Korea (독도 주변해약에서 삼중자망으로 어획한 어류의 종조성 및 계절변동)

  • Lee, Hae-Won;Hong, Byung-Kyu;Sohn, Myong-Ho;Chun, Young-Yull;Lee, Dong-Woo;Choi, Young-Min;Hwang, Kang-Seok
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.43 no.6
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    • pp.693-704
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    • 2010
  • Seasonal variation in species composition around Dokdo, East Sea of Korea, was investigated using trammel-net catches, from 2006 to 2009. A total of 53 fish species belonging to 23 families in 12 orders were captured; the orders Perciformes (12 families, 22 species) and Scorpaeniformes (four families, 22 species) were dominant. Between 2008 and 2009, 43 species were collected by trammel net. The number of species was highest in August 2009 (25 species) and lowest in February 2009 (11 species). The number of individuals and total biomass peaked in November 2009. Diversity indices for fish catches were highest in August 2008 (2.4368) and lowest in November 2009 (0.4253). The dominant species were Thamnaconus modestus and Sebastes schlegeli. Hierarchical clustering analysis showed five fish groups, with frequency and number of individuals similar to results of correspondence analysis (CA), which showed a closer relationship to the year term than the season term. CA showed that temperature was an important factor influencing fish species richness and abundance. Three main fish assemblage types coexisted around Dokdo: an East Sea coastal fish assemblage, a subtropical fish assemblage, and a cold water fish assemblage.

Bird Diversity and Environmental Correlates in the Mulchat-oream Wetlands of the Jeju Islands, South Korea

  • Jeong, Young-Hun;Jin, Seon-Deok;Banjade, Maniram;Son, Se-Hwan;Choi, Sung-Hoon;Choi, Sung-Hwan;Oh, Hong-Shik
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • v.3 no.2
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    • pp.77-83
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    • 2022
  • This study was conducted from March 2018 to December 2019 to identify bird diversity and environmental correlates within the Mulchat-oream wetlands in the Jeju Islands of South Korea. A total of 255 individual belonging to 37 species were recorded form Mulchat-oream. The observation produced a species diversity of 3.14, species richness of 6.54 and species evenness of 0.88 in 2018, and in 2019, the observed species diversity was 3.02, species richness was 6.56 and species evenness was 0.84. The highly dominant species are composed of Passeriformes. The absence of diverse submerged plants, deep water depth and isolated geographical locations makes difficult for aquatic birds to prefer this area, and this has resulted in the dominance of Passeriformes. The appearance of the birds was the lowest in the winter and highest during the summer. The analysis showed that the species richness and evenness increased with an increase in temperature and precipitation. However, the number of species appearing during Mulchat-oream significantly dependent on the temperature (P<0.001, df=2). To date, there has been little research on bird diversity together with environmental factors for the Hallasan National Park. This study shows the environmental factors and seasonal patterns that affect bird population.

Endomycorrhizal Fungi identified on the Soils in Forest and Coast Areas (산림 및 해안지역에서 발견된 내생균근)

  • Eom, Ahn-Heum;Lee, Sang-Sun
    • The Korean Journal of Mycology
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    • v.17 no.1
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    • pp.14-20
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    • 1989
  • The presence of endomycorrhizal fungi was examined on the soils collected from the followings; Cryptomeria japonica dominant forest (Wan San Park, Jun Ju city) and two coast areas (Digitaria sanginalis dominant; Sin Chang Ri, Young Il Kun and Pragmited communis dominant; Sap Kyo Cheon, A San). Six species in Endogonales were identified; Glomus intraradices, G. occulum, G. clarum, Acaulospora bireticulata, Scutellospora aurigloba, and Sc. gilmorei.

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Dominant Floristic Composition and its Distribution in the Upper Keum River Basin (금강 상류유역의 우점 식물상 조성과 분포)

  • Beon, Mu-Sup;Oh, Hyun-Kyung;Kim, Young-Ha
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.8 no.4
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    • pp.52-67
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    • 2005
  • The flora of the studied basin in the upper Keum River was listed as 237taxa; 63families, 162genera, 212species, 22varieties and 3forms. Based on the list of the ecosystem disturbance plants by the Ministry of Environment, 4taxa were recorded in the studied basin : Paspalum distichum(Gramineae), Paspalum distichum var. indutum(Gramineae), Ambrosia artemisiifolia var. elatior(Compositae), Ambrosia trifida(Compositae). Naturalized plants was listed as 54taxa; 16families, 41genera, 51species, 3varieties and naturalization index was 22.8percent of 1/4 the vascular plants. Upper Keum River was dominant floristic : indicator species were Salix gracilistyla community, Phragmites japonica community, native plants were Morus alba community, Spiraea prunifolia for. simpliciflora community, planting plants were Populus euramericana community, naturalized plants were Solidago serotina community, Helianthus tuberosus community.

The Flora of Jangsanbong (장산봉(부산)의 식물상)

  • Lee, Jung-Hoon;Moon, Sung-Gi
    • Journal of Environmental Science International
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    • v.16 no.8
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    • pp.881-889
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    • 2007
  • The flora of vascular plants in Jangsanbong located at Busan Metropolitan City was investigated from April 2003 to April 2004. Vascular plants in the surveyed area were 254 taxa that belonged to 78 families, 175 genera, 218 species, 34 varieties, and 2 forma. Among them, 20 taxa of evergreen broad trees, 31 taxa of naturalized plants were identified, and especially Rubus trifidus was first recorded in Busan. In the upper part of a circular road dominant species was Pinus thunbergii. In the lower part of a circular road and the coastal area, dominant species were Platycarya strobilacea, Clerodendron trichotomum, Euscaphis japonica, Quercus aliena, Quercus dentata, Mallotus japonicus, which distribute mainly in the subtropical and temperate zone. In the surveyed area, the canopy consistsed of tall trees, Pinus thunbergii, and the understratum were trees such as Eurya japonica, Ficus erecta, Ligustrum japonicum, Prunus sargentii, and Celtis sinensis var. japonica.

Composition of the Gastrointestinal Microflora in Korean Breast-fed and Formula -fed Newborn Infants (수유방법에 따른 한국 신생아의 장내균총 조성에 관한 연구)

  • 문수재
    • Journal of Nutrition and Health
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    • v.31 no.1
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    • pp.80-87
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    • 1998
  • Intestinal microflora in 17 breast-fed(BF) and 14 formula-fed (FF) newborn infants at about 1 week after birth were investigated to determine the floral differences of the two lactation groups. The fecal conditions were significantly different between the two groups in that the number of subjects who showed watery feces, and the times of defecation per day, were higher in the BF group. In addition, the mean fecal PH of the BF group was lower than that of the FF group. The dominant species in the BF groups which showed the highest count among the species of microflora was bifidobacteria , while the dominant species in the FF group was streptococci. The frequency of staphylococci and the count of bifidobacteria were significantly higher in the BF group. However, the frquencies of streptococci and Peptococcaceae were higher in the FF group. Through the differences were not significant, the frequency of bvifidobacteria and the count of staphylococci were higher in BF group, whereas the frequencies of bacteriodes, clostridia, enterobacter and the count of clostridia were higher in FF group.

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